PNG : The definitive guide

PNG (Portable Network Graphics) is the next-generation graphics file format for the Web. Designed as an open-source format to replace GIF (which uses a proprietary compression scheme for which software makers must pay a licensing fee), PNG is better, smaller, more extensible, and FREE.

Already supported by major software like Macromedia Fireworks, Adobe Photoshop, and Microsoft Office 98, as well as Netscape Navigator and Microsoft Internet Explorer, PNG is the next big thing in computer graphics. Similar to the GIF and TIFF formats, but far better, PNG will soon become the preferred file format for color-critical web images and high-quality graphics interchange. Even for noncritical images, PNG will likely replace GIF as the standard web format. PNG supports lossless compression, variable transparency information, and a range of color depths. PNG also provides direct support for gamma correction, the cross-platform control of image "brightness," and transparency. PNG: The Definitive Guide addresses the needs of graphic designers who want to get the most out of the format and programmers who want to add full PNG-support to their own applications. Specifically, Roelofs covers implementing PNG with the libpng C library. The book includes explanations of important improvements with PNG, such as gamma correction and the standard color spaces for precise reproduction of image colors on a wide range of systems.

PNG: The Definitive Guide is the first book devoted exclusively to teaching and documenting the important new format, PNG. It is an indispensable compendium for Web content developers and is chock full of examples, sample code, and practical hands-on advice.

Table of contents

Preface

Chapter 1: An Introduction to PNG

Overview of Image Properties

What Is PNG Good For?

Case Study of a PNG-Supporting Image Editor

Chapter 2: Applications: WWW Browsers and Servers

WWW Browsers

WWW Servers

Chapter 3: Applications: Image Viewers

Windows 95/98/NT

Windows 3.x

VMS

Unix

OS/2

Macintosh

Java

DOS

BeOS

Atari

Amiga

Acorn RISC OS

Chapter 4: Applications: Image Editors

Photoshop 5

Photoshop 4

ImageReady

Paint Shop Pro

The Gimp

Other Image Editors

Chapter 5: Applications: Image Converters

pngcrush

pnmtopng

gif2png

Tiff2png

pngcheck

Other Conversion Programs

Chapter 6: Applications: VRML Browsers and Other 3D Apps

Cosmo Player

WorldView/MSVRML

blaxxun Contact

Viscape Universal

LibVRML97/Lookat

FreeWRL

VRMLView

Other VRML Browsers

Other 3D Applications

Chapter 7: History of the Portable Network Graphics Format

Anatomy of an Internet Working Group

Implementation

MNG

Mainstream Support and Present Status

Chapter 8: PNG Basics

Chunks

PNG Signature

A Word on Color Representation

The Simplest PNG

PNG Image Types

Interlacing and Progressive Display

Chapter 9: Compression and Filtering

Filtering

The Deflate Compression Algorithm

Real-World Comparisons

Practical Compression Tips

Chapter 10: Gamma Correction and Precision Color

Transfer Functions and Gamma

The gAMA Chunk

Encoding Gamma

Gamma Gotchas

Chromaticity

Color Management Systems and sRGB

ICC Profiles

Chapter 11: PNG Options and Extensions

Background Color (bKGD)

Timestamp (tIME)

Latin-1 Text Annotations (tEXt, zTXt)

International Text Annotations (iTXt)

Histogram (hIST)

Suggested Palette (sPLT)

Significant Bits (sBIT)

Physical Pixel Dimensions (pHYs)

Physical Scale (sCAL)

Image Offset (oFFs)

Pixel Calibration (pCAL)

Fractal Parameters (fRAc)

GIF Conversion Info (gIFg, gIFx)

GIF Plain Text (gIFt)

Other Chunks

Chapter 12: Multiple-Image Network Graphics

Common Applications of MNG

MNG Structure

The Simplest MNG

An Animated MNG

An Algorithmic MNG

A JPEG Image with Transparency

MNG Applications

The Future?

Chapter 13: Reading PNG Images

A libpng-Based, PNG-Reading Demo Program

Preliminaries

readpng_init()

readpng_get_bgcolor()

Design Decisions

Gamma and Color Correction

readpng_get_image()

readpng_cleanup()

Compositing and Displaying the Image

Getting the Source Code

Alternative Approaches

Chapter 14: Reading PNG Images Progressively

Preliminaries

readpng2_init()

readpng2_decode_data()

readpng2_info_callback()

readpng2_row_callback()

Compositing and Displaying the Image

readpng2_end_callback()

readpng2_cleanup()

Getting the Source Code

Chapter 15: Writing PNG Images

A libpng-Based, PNG-Writing Demo Program

Gamma Correction

Text Chunks

writepng_version_info()

writepng_init()

Interlaced PNG: writepng_encode_image()

Noninterlaced PNG: writepng_encode_row()

writepng_cleanup()

Getting the Source Code

Chapter 16: Other Libraries and Concluding Remarks

Cross-Platform Libraries

Windows-Specific Libraries

Concluding Remarks

.TC 0 "References"

Glossary

Index